<!DOCTYPE html>
<html lang="en">
<head>
<meta content="width=device-width, initial-scale=1" charset="utf-8" />
<title>Benchmarking and comparing DwarFS</title>
<link href="/style.css" type="text/css" rel="stylesheet" />
<link href="/prism.css" type="text/css" rel="stylesheet" />
</head>
<body class="line-numbers">
<h1 id="benchmarking-and-comparing-dwarfs">Benchmarking and
comparing DwarFS</h1>
<p>DwarFS is a filesystem developed by the user mhx on GitHub
[1], which is self-described as "A fast high compression
read-only file system for Linux, Windows, and macOS." One of my
ideas for blendOS was to layer different packages, and combined
with its compression and option to be mounted as a FUSE-based
filesystem, it's an appealing option for this use case - blendOS
is immutable, so it might as well have some compression.</p>
<h2 id="methodology">Methodology</h2>
<p>The datasets being used for this test will be the
following:</p>
<ul>
<li>25 GiB of null data (just <code>00000000</code> in
binary)</li>
<li>25 GiB of random data<a href="#fn1" class="footnote-ref"
id="fnref1" role="doc-noteref"><sup>1</sup></a></li>
<li>Data for a 100 million-sided regular polygon; ~26.5 GiB<a
href="#fn2" class="footnote-ref" id="fnref2"
role="doc-noteref"><sup>2</sup></a></li>
<li>The current Linux longterm release source (<a
href="https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.6.58.tar.xz">6.6.58</a>
[2]); ~1.5 GB</li>
<li>For some rough latency testing:
<ul>
<li>1024 4 KiB files filled with null data (again, just
<code>00000000</code> in binary)</li>
<li>1024 4 KiB files filled with random data</li>
</ul></li>
</ul>
<p>All this data should cover both latency and read speed
testing for data that compresses differently - extremely
compressible files with null data, decently compressible files,
and random data which can't be compressed well.</p>
<h3 id="what-filesystems">What filesystems?</h3>
<p>I'll be benchmarking DwarFS, fuse-archive (with tar files),
and btrfs. In some early, basic testing, I found that mounting
any <em>compressed</em> archives with <code>fuse-archive</code>,
a tool for mounting archive file formats as read-only
filesystems, took far too long. Additionally, being FUSE-based,
these would have slightly worse performance than kernel
filesystems, so I tried to use a FUSE driver as well for btrfs.
Unforunately, I ran into a bug, so I won't be able to quite do
an equivalent test; btrfs will only be running in the
kernel.</p>
<p>During said early testing, I also ran into the fact that most
compressed archives, like Gzip-compressed tar archives, also
took far too long to <em>create</em>, because Gzip is
single-threaded. So all the options with no chance of being used
have been marked off, and I'll only be looking into these
three.</p>
<p>DwarFS also took far too long to create on its default
setting, but on compression level 1, it's much faster -
11m2.738s for the ~80 GiB total, and considering</p>
<h2 id="running-the-benchmark">Running the benchmark</h2>
<p>First installed it by cloning the repository, installing it
using Cargo, then added its completions to fish (just for this
session):</p>
<div class="sourceCode" id="cb2"><pre
class="language-sh"><code class="language-bash"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="fu">git</span> clone https://git.askiiart.net/askiiart/disk-read-benchmark</span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="bu">cd</span> ./disk-read-benchmark</span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="ex">cargo</span> install <span class="at">--path</span> .</span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="ex">disk-read-benchmark</span> generate-fish-completions <span class="kw">|</span> <span class="bu">source</span></span></code></pre></div>
<p>Then I prepared all the data:</p>
<div class="sourceCode" id="cb3"><pre
class="language-sh"><code class="language-bash"><span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="ex">disk-read-benchmark</span> prep-dirs</span>
<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a><span class="ex">disk-read-benchmark</span> grab-data</span>
<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a><span class="ex">./prepare.sh</span></span></code></pre></div>
<p><code>disk-read-benchmark</code> prepares all the
directories, generates the data to be used for testing, then
<code>./prepare.sh</code> uses the data to generate the DwarFS
and tar archives.</p>
<p>To run it, I just ran this:</p>
<div class="sourceCode" id="cb4"><pre
class="language-sh"><code class="language-bash"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="ex">disk-read-benchmark</span> benchmark</span></code></pre></div>
<p>Which outputs the data at
<code>data/benchmark-data.csv</code> and
<code>data/bulk.csv</code> for the single and bulk files,
respectively.</p>
<h2 id="results">Results</h2>
<p>After processing <a
href="/assets/benchmarking-dwarfs/data/">the data</a> with <a
href="/assets/benchmarking-dwarfs/process-data.py">this
script</a> to make it a bit easier, I put the resulting graphs
in here ↓</p>
<h3 id="sequential-read">Sequential read</h3>
<h3 id="random-read">Random read</h3>
<h3 id="sequential-read-latency">Sequential read latency</h3>
<div>
<canvas id="seq_read_latency_chart" class="chart">
</canvas>
</div>
<h3 id="random-read-latency">Random read latency</h3>
<p>The FUSE-based filesystems run into a bit of trouble here -
with incompressible data, DwarFS has a hard time keeping up for
some reason, despite keeping up just fine with larger random
reads on the same data, and so it takes 3 to 4 seconds to run
random read latency testing on the 25 GiB random file.
Meanwhile, when testing random read latency in
<code>fuse-archive</code> pretty much just dies, becoming
ridiculously slow (even compared to DwarFS), so I didn't test
its random read latency at all and just had its results put as 0
milliseconds.</p>
<h3 id="summary-and-notes">Summary and notes</h3>
<h2 id="sources">Sources</h2>
<ol type="1">
<li><a href="https://github.com/mhx/dwarfs"
class="uri">https://github.com/mhx/dwarfs</a></li>
<li><a href="https://www.kernel.org/"
class="uri">https://www.kernel.org/</a></li>
<li><a
href="https://git.askiiart.net/askiiart/disk-read-benchmark"
class="uri">https://git.askiiart.net/askiiart/disk-read-benchmark</a></li>
<li><a
href="https://git.askiiart.net/confused_ace_noises/maths-demos/src/branch/headless-deterministic"
class="uri">https://git.askiiart.net/confused_ace_noises/maths-demos/src/branch/headless-deterministic</a></li>
</ol>
<h2 id="footnotes">Footnotes</h2>
<!-- JavaScript for graphs goes hereeeeeee -->
<!-- EXAMPLE HERE -->
<script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
<script>
let ctx = document.getElementById('seq_read_latency_chart');
const labels = ['Null 25 GiB file', 'Random 25 GiB file', '100 million-sided polygon data', 'Linux LTS kernel']
let data = [
{
label: 'DwarFS',
data: [0.37114600000000003, 14.15143, 2.95083, 0.001523],
backgroundColor: 'rgb(255, 99, 132)',
},
{
label: 'fuse-archive (tar)',
data: [0.393568, 0.397626, 0.07750499999999999, 0.0012230000000000001],
backgroundColor: 'rgb(75, 192, 192)',
},
{
label: 'Btrfs',
data: [0.027922000000000002, 0.290906, 0.14088399999999998, 0.0013930000000000001],
backgroundColor: 'rgb(54, 162, 235)',
},
]
let config = {
type: 'bar',
data: {
datasets: data,
labels
},
options: {
plugins: {
title: {
display: true,
text: 'Sequential Read Latency - in ms'
},
},
responsive: true,
interaction: {
intersect: false,
},
}
};
Chart.defaults.borderColor = "#eee"
Chart.defaults.color = "#eee";
new Chart(ctx, config);
</script>
<section id="footnotes"
class="footnotes footnotes-end-of-document" role="doc-endnotes">
<hr />
<ol>
<li id="fn1"><p>My code can generate up to 25 GB/s. However, it
does random writes to my drive, which is <em>much</em> slower.
So on one hand, you could say my code is so amazingly fast that
current day technologies simply can't keep up. Or you could say
that I have no idea how to code for real world scenarios.<a
href="#fnref1" class="footnote-back"
role="doc-backlink">↩︎</a></p></li>
<li id="fn2">This data is from a modified version of an
abandoned math demonstration program [4] made by a friend; it
generates regular polygons and writes their data to a file. I
chose this because it was an artificial and reproducible yet
fairly compressible dataset (without being extremely
compressible like null data).
<details open>
<summary>
3-sided regular polygon data
</summary>
<br>
<!-- I put it in here just as a `style`, it didn't work. I put it in as a div with that `style`, it didn't work. I put it in as a div of that class which has those properties in style.css, it works -->
<!-- i hate webdev i hate webdev i hate webdev i hate webdev i hate webdev i hate webdev -->
<div class="force-word-wrap">
<pre><code>[Vertex { position: Pos([0.5, 0.0, 0.0]), color: Col([0.5310667, 0.7112941, 0.7138775]) }, Vertex { position: Pos([-0.25000003, 0.4330127, 0.0]), color: Col([0.7492257, 0.3142163, 0.49905664]) }, Vertex { position: Pos([0.0, 0.0, 0.0]), color: Col([0.2046682, 0.25598457, 0.72071356]) }, Vertex { position: Pos([-0.25000003, 0.4330127, 0.0]), color: Col([0.6389981, 0.5204368, 0.077735074]) }, Vertex { position: Pos([-0.24999996, -0.43301272, 0.0]), color: Col([0.8869035, 0.30709425, 0.8658899]) }, Vertex { position: Pos([0.0, 0.0, 0.0]), color: Col([0.2046682, 0.25598457, 0.72071356]) }, Vertex { position: Pos([-0.24999996, -0.43301272, 0.0]), color: Col([0.6236294, 0.03584433, 0.7590722]) }, Vertex { position: Pos([0.5, 8.742278e-8, 0.0]), color: Col([0.6105084, 0.3593351, 0.85544324]) }, Vertex { position: Pos([0.0, 0.0, 0.0]), color: Col([0.2046682, 0.25598457, 0.72071356]) }]</code></pre>
</div>
</details>
<a href="#fnref2" class="footnote-back"
role="doc-backlink">↩︎</a></li>
</ol>
</section>
<iframe src="https://john.citrons.xyz/embed?ref=askiiart.net" style="margin-left:auto;display:block;margin-right:auto;max-width:732px;width:100%;height:94px;border:none;"></iframe>
<script src="/prism.js"></script>
</body>
<footer>
<p><a href="https://git.askiiart.net/askiiart/engl-2311-blog">Source code</a> | <a href="/feed.xml">RSS</a> | <a href="/glossary.html">Glossary</a> | <a href="/about.html">About</a></p>
<small>Image captions are the same as the alt text; assuming you're sighted, you can most likely ignore them.</small>
</footer>
</html>